Glider coupling



Aug. 29, 1944. J. F. DREscHER 2,355,920

l GLIDER coUPLING Filed Aug. I27.' 1943 5 sheets-sheet 1 Aug. 29, 1944. J. F. DREscHER GLIDER coUPLINe Filed Aug. 27, 1943 5 Sheets-Sheet 2 |NvENToR. H/v DQESCHER,

ATroRN EY.

Aug. 29, 1944.

J. F. DREscHER GLIDER COULING Filed Aug. 27, 1943 5 Sheets-Sheet 5 Aug. 29, 1944. J. F. DREscHER 2,355,920

GLIDER COUPLING Filed Aug. 27, 1943 l 5 Sheets-Sheet 4 l fr z-H/v E' .Dee-50H52, INVENTOR.

j ATTORNEY.

Aug. 29, 1944. J. F. DREscHER 2,356,920

GLIDER GOUPLING Filed. Aug. 27, 1943 5v Sheets-Sheet 5 H/v DQEscHs/e,

INVENTOR.

ATTORNEY.

Patented Aug. 29, 1944 UNITED srlxrlzsl PATENT OFFICE GLIDER COUPLING John F. Drescher, Los Angeles, Calif.

Application AugustV 27, 1943, Serial No. 500,300

20 Claims.

This invention relates to a releasable coupling for towing gliders behind airplanes or behind other gliders. It is conventional to employ for such purposes a manually operated quick detachable coupling associated with a towing bar. The bar is mounted either in the nose of the glider or the tail of the airplane, or in both, whereby the towing cable may be instantly released from either craft or from both of them. Manualv release is attained by pulling on a cable. This has some disadvantages, namely a cable of any length to a remote part of the glider adds weight and opportunity for fouling and moreover is usually operable only from one position in the glider.

It is a [primary object of my invention to provide an electrical release for a glider towing bar coupling. It may be wired for operation fro-m any of several locations in the glider, or connected through the agency of the towing cable for remote control in the towing airplane, or may be augmented by a radio control.

A further object of the invention is to provide an electrical release which may be installed in a conventional glider towing bar without materially modifying the external physical design or proportions of such bar. It is possible to install a battery for operating the release in the bar itself, but this is not normally necessary as the glider is usually equipped with an electrical system. Very slight external appendages are required, and the electrical mechanism is exceptionally light in weight .and compact.

A further object of my invention, in a modified form, is. toprovide a glider coupling of completely novelV construction and improved operation useful for the same type of duty as is the first form, but designed to satisfactorily operate under a much heavier load than is feasible with the first form.

Further objects of my modied formof invention are to incorporate anovel form of coupling jaw in which the normal draft pressure at the rear ends of the jawis imposed upon rollerbearings which may be withdrawn upon either electrical or manual release to free the parts of the jaw for opening to release the cable.

A still further object of the modiiied form of invention is to provide a coupling of the character described in which there are no laterally projecting operating, parts, the mechanism being housed within a streamlined or bullet type of shell whereby installation is facilitated and external operating parts are reduced to a minimum 'and present only at the nose and tail of the device.

These and additional objects of my invention in both forms will become more apparent from a further consideration of the description and drawings.

In the drawings:

Figure 1 is a side elevational View of a towing bar coupling embodying my invention, mounted in the nose of a glider.

Figure 2 is a vertical sectional view of the towing bar coupling showing the mechanism in locked position.

Figure 3 is a top plan View of the bar with the parts in the same position as in Figure 2.

Figure 4 is a vertical sectional `View similar to Figure 2 showing the mechanism in releasing position. v

Figure 5 is an enlarged fragmentary vertical sectional view illustrating an operating solenoid and immediately associated parts of myV device.

Figure 6 is a cross-sectional view taken. on the 'line 6-6 of Figure 5.

Figure 7 is. a longitudinal sectional View of' a modified forni of my invention showing the mechanism in locked position.

`Figure 8 is a view similar to Figure 7 showing the mechanism in releasing position.

Figure 9 is a top plan view of the modified form of my device illustrating its relationship to a mounting in the glider and a, towing cable.

Figure l10 is a cross-sectional view taken on the line Ill-I0 of Figure 7.

Figure 11' is a side elevation of a setting cam device taken in the direction of the arrows Il in Figure 10.

Figure 12 is a` cross-sectionalview taken on the line I2-I2 of Figure '7.

Figure 13 is a Vertical sectional view through ,the forward regionV of the shell housing the mechanism of the modied form.

Figure 14 is a horizontal Sectional view of the same region, taken on the line |4-l4 of Figure 13.

Figure 15 is a vertical sectional View of a setting` ring for operating the cam.

Figure 16 is another sectional. view of the same taken on the line Iii-f1.6 of Figure 15.

Referring to the form of invention illustrated in Figures 1 to 6,` the towing device I5 is shown installed in a glider I6, and retaining the ring Il of a towing cable I8.

The device I5 comprises an elongated sleeve or tube 20 provided with-any suitable mounting means such as clamps- 21| which may be bolted to any suitable element of the glider, asv for eX- ample a frame piece 22.

Mounted to swivel within the forward end of the tube 20 is a coupling head 23 formed with diametrically opposed longitudinal slots 24 and 25. The slotted head is bifurcated at its forward end to receive the shoulders of a pair of cooperating jaw members 26 and 21 which are pivotally mounted by means of pivot pin 28. The opposed slots 24 and 25 are the same width as, and merge into the end bifurcation. Thus the shoulders of the jaw members are disposed within th bifurcation, and the rear ends of these members may be received in the slots. The jaw member 26 is centrally slotted as at 29 to receive the shoulder of the narrower jaw member 21. 'I'he forward end of the jaw member 26 is also recessed `as at 36 to provide an interlocking contact with the forward end 3| of the jaw member 21 whereby when the jaws are closed the ring |1 is retained therebetween.

It is obvious from the illustration, that the jaws are mounted scissors fashion so that if the rear ends thereof are held closed the front ends will be likewise closed.

The rear ends of the jaws are retained in closed position in the slots 24 and 25 by a sliding collar 35 urged forward by a compression spring 36 the rear end of which abuts against a bracket 31. Forward movement of the collar 35 is limited by oppositely disposed lugs 38 which may be the ends or heads oil a pin 38a extending through the coupling head.

The bracket 31 is secured `.upon the tube 20 by a pair of bolts 39 which pass through the tube. These bolts are tangential to a groove 39a in the rear end of the head 23 whereby the swivel connection between the head and the tube previously referred to is attained.

A yoke 40 is pivotally mounted by pins 4| on the sliding collar 35, and is pivotally anchored at its lower end upon. a bolt'I 42 extending between horizontal projections 43 of the bracket 31. A cable 45 is attached to the upper end of the yoke 40, and by pulling on the cable 45 the slidable collar 35 may be withdrawn against action of the spring 36 to free the jaws 26 and 21.

' The foregoing combination of elements which has been somewhat brieiiy described, embodies a substantially conventional manually or cable operated glider towbar or coupling.

My invention resides in the application of an electrical releasing mechanism in combination with the foregoing, incorporating some necessary modification of the conventional coupling, and the invention also embraces the electrical mechanism per se. By the term electrical mechanism, I imply the necessary associated mechanical parts, and the whole may be designated an electrically operated mechanism.

A stop member 50 isriveted, bolted, welded, or otherwise secured in the tube 20 near the bracket 31. This stop member provides an abutment for a strong compression spring The compression spring 5| must be ample to overcome the resistance of the other spring 36 as well as the frictional resistance offered by the coupling parts in closed position when sliding the collar 35 from locking to releasing position.

'Ihe rear end of the-spring 5| engages a sliding hollow block 52. An eye bolt 53 which passes through a longitudinal slot 54 in the tube 20 is threaded into the block 52 and governs the reciprocal stroke of the block by engagement with opposite ends of the slot 54.

A `telescoping linkage 55 interconnects the eye bolt 53 and the yoke 45.

When the sliding block 52 is at its forward position, as illustrated in Figure 2, the linkage 55 is slightly telescoped or at least exerts no pulling effect on the yoke 40, thus permitting the spring 36 to advance the collar 35 into its forward or locking position. When the sliding block 52 is forced by the spring 5| to its rearward position, as illustrated in Figure 4, the link 55 pulls the yoke 40 forward against compression of the spring 36 and retracts the collar 35 into unlocked or releasing position.

If the sliding block is unrestrained the spring 5| will shift it rearwardli7` for such purpose. This block is held in its forward position (Figure 2) and released for rearward shifting (Figure 4) by my electrically operated mechanism generally designated by the reference numeral'60.

This mechanism comprises a trigger 6| pivotally mounted at 62 within the tube, adapted to engage a latch pin 63 in the sliding block 52, and controlled by a solenoid 64.

The rear end of the trigger 6| is supportable `on either one of two steps 65 and 66 of a rocker arm 61 which is pivotally mounted at 68 in a slotted mounting 69. When the trigger rests on the upper step 65 as illustrated in Figures 2 and 5, an oblique face 10 at the forward end of the trigger engages the pin 63 in the sliding block 52 and restrains the block from shifting rearwardly under influence of the spring 5|. When the trigger is permitted to drop to the second or lower step 66 the force of the spring 5| urges the block 52 rearwardly and the pin 63 pushes against the trigger face 10 with a cam action elevating the forward end of the trigger and permitting the pin 63 to pass into the position shown in Figure 4.

' The rocker arm 61 is normally retained in a forward position, as shown in Figures 2 and 5, wherein the trigger must rest on the upper step 65, by the solenoid armature 15 which is coupled to the rocker arm 61 (as later described) and is advanced by an internal solenoid spring 16. Thus when the solenoid remains deenergized the trigger is maintained in restraining position and when the solenoid is energized the rocker arm 61 is shifted, permitting the rear end of the trigger to fall, and releasing the pin 63, which in turn through the various associated parts already described causes the collar 35 to shift rearwardly and unlock the jaws 26 and 21.

Y Iemploy a novel solenoid, some of the features of which are disclosed in my copending application for Bomb Shackle filed December 15, 1942, Serial No.,469,077. It comprises a soft steel core having a relatively wide ange base or end 6| land its opposite end terminating in a frustoconical tip 82. It is hollow for the purpose of accommodating the compression spring 16. The

spring is bronze or other non-magnetic material.

Thecylindrical extension of the core is enclosed by a brass or non-magnetic tube 11 which is offset at one end to form a seat for an iron head 18. The winding 83 encircles the tube 11, and a metal case 84 encloses the parts described. The metal case 84 is cylindrical in shape to form a snug t in the bore of the tube tating installation in the tube and at the same time aiding in the dissipation of heat generated in the solenoid by dispersion thereof into the tube. An iron plunger or armature .previously indicated by the reference numeral 15 is reciprocably located within the iron head 18 and the winding 83, is drawn in when the solenoid is energized, and'returned by the spring 16 when deenergized. The iron plunger is formed at its inner end with a hollow cone 86 complementary to the frustoconical end 82 of the core, and has an ear 81 slotted to receive thev pin 89 of the rocker arm 61.

The structure illustrated and described is com-v pact, operates with alight spring, requires a minimum of current, iseasi-ly mounted Ywithin the cylindrical tube 20 and insures rapid and effective dissipation of heat.

The forward end of the trigger is formed with al hook element 90 having an inclinedY face 9|, the latter of which functions in connection with the cocking of the device.

In operation, assuming that the electrically operating releasing mechanism is cocked, the ring I1 may be inserted in the jaws while the collar 35 is manually retracted, the rear portions of the jawsl are seated in the grooves of the cou-4 pling head, and the collar is allowed to advance under influence of the spring 36 into locking position. j

-In order to cock the electrically operated releasing mechanism the block 52` is slid forward against compression of the spring by exerting pressure on the eye bolt 53. It is noted that the slot 54 is somewhat longer than necessary for the nal cocked `position of the eye bolt to permit a slight over-'travel of the eye bolt. In this over-travel of the eye bolt the pin 63 in the block 52 is brought against the inclined face 9| of the forward end of the trigger and the cam action of the pin on the trigger face draws the forward end of the trigger down thereby elevating the rear end of the trigger, and the spring 16 in the solenoid forces the plunger outwardly there,- by tipping the rocker arm 61 forwardly so that the rear end of the trigger cornes to rest in the upper step 65 of the rocker arm'. Thereupon pressure o-n the eye bolt may be released and it will slide slightly toward the rear until the pin 63 comes into locking engagementl with the face of the trigger.

The mechanism will remain lin theA locked and cocked position, andi the jaws may be freed for uncoupling the tow cable ring either by pullingl on the cable 45 as previously described, or by energizing the solenoid, in which latter case the rear end of theY triggerV is permitted to drop from the upper step 65to the lower stepy S6 there.- by freeing the pin 63 so that the sliding block` 52 may shift rearwardly under infiuence of they spring 5| and consequently through the eyebol-t i 53 and the link 55 dr'aw the yoke 40y rearwardly, which retractsthe collar 3'5y and thereby releases thev jaws. Y

An electrica] release of the character 'which' I disclose and claim has the advantages not only of being controllable from any desired pointin the` glider but also remotely from theA gliderby means lof, for example, electrical cable connection tothe towing airplane, or even by radio,

aSSllmng'a suitable control device in connection 5" with the electrically operated' mechanism "by which the solenoid will be energized.

Themodied form vof my invention is shown in Figures '7 to 16 inclusive. As before indicated, it is more compact than the other form and is con# structed for much heavier duty. Y

Referring 'to Figure 9 my 'modied device comprises externally a shell |00 formed with a mounting ange |0I, and optionalv mounting bolt holes IOIa, and embodying a; cooking collar |02 and coupling jaws. |03. VThese jaws engage a ring |05 of a, towing cable |06.

The shell `|00 has an overall configuration similar to that of a bullet.- It rprovides a cylindrical chamber |01 with extending cylindrical recesses |08, and |09, and is formed with a vertical slot I I0, and a forward vertical slot I I I. The shell |00 is reduced in external diameter from a shoulder ||2 to the forward end for purposes hereinafter described, and there is an intermediate annular ange ||3 the purpose of which will also become more fully apparent.

The jaws |03 will be for convenience identified as an upper jaw |03a and a lower jaw |03b. They are pivotally mounted upon a heavy pin |I4 within the slot III of the shell. Jaw |03a is formed with a recess ||5 adapted to receive ward end of a slide assembly which has a sliding fit within the flange I I3l and recess or bore |09.

When the slide assembly |20 is forward, as in the position shown in Figure '1, the roller bearings engage the jaws and the jaws are locked. When the assembly is. rearward as shown in Figure 8 the roller bearings are free of the jaws and the jaws open as showny in Figure 8.

The assembly |20 comprises a cylindrical sleeve I2| provided at its rear end with a collar |22 against which one end of-a spring |23 abuts. The opposite end of the spring presses against the wall of thevflangeY I3; The normal tendency of the spring, and it has vsufficient strength for Y40 the purpose, is to shift the assembly |20 rearwardly for unlocking the jaws. It can'be restrained for keeping the jaws in locked position by a trigger |25.

This `trigger isA pivotally mounted in the sleeve |2I at |26.` The rear end of the trigger is recessed to engage a latch pin |21 which is diametrically positioned in the shell |00, and the forward end is adapted to engage a rocker arm. |28. The rocker armf is pivoted at |29 on a bracket |30 and is adapted to be actuated by a Kplunger |3I of a solenoid'lilZ.` This solenoid is the same type as that described in more detail inthe other .form of the invention. Likewise the rocker arm |20 is formed with an upper step |33 and a lower step I 34. When the forward end of the trigger rests on the upper step |33 the rear end isheld .in engagement `with the latch pin |21. When the solenoid is energized-to swing the rocker arm so that the forward end of the-trigger drops into the lower stepy I34the. rear endof the trigger is. freed toV escapev -past the vlatching pin I.2:1 and` they shiftable assembly |20 willrmove rearwardly under influence of the spring |23.

'I'he same action maybe accomplished manually by a manual release |40. This comprises a rod |4| to which is coupled a linkage generally designated Ii42 which is pivotally connected to a pawl |43..v Thev latter is pivotally mounted at |44 on the bracket |30. When the rod is pulled inV alefthand directiomas shown in Figure 7, this causes the pawl |43 to rotate and the upper end thereof toengage the rocker army |28 for rotating same clockwise, the san-1eas if the rocker armwere thus actuatedV by energizing the solenoid. The linkage '|42. includes three springs |50, 15|, and |52. Of these, spring |50 is the strongest, spring is'of medium strength and spring |52 is the weakest. Spring |50 extends between the shoulder of a bearing bushing |53 and a flange |54 at the end of the rod |4|. Spring|5| links rod 4| and a shaft |55. Spring |52 is disposed between a stop member |56 mounted in the sleeve |2| and a stop member |51 on the shaft |55.

The purpose of this combination spring, rod and shaft arrangement is to absorb over-drive oi the rod |4| and thus protect the more delicate operating mechanism such as the pawl |43, etc. from injury, also to provide iiexibility when the slide assembly shifts rearwardly.

In the rst place, tension of the spring |50 must be initially overcome in shifting the rod I4 When its resistance is overcome the medium strength spring |5| shiftsthe shaft |55 against tension of the weakest spring |52. -Thus shocks are absorbed, and the springs not only protect the more sensitive working parts against shock but are so adjusted in tension that after the initial movement of the rod |4| suicient to actuate the pawl |43 and trip the trigger any further movement encounters heavy resistance especially by the strong spring |50.

Assuming the working parts are in the position shown in Figure 8, in unlocked or uncoupled position, and it is desired to couple a towing cablering, the ring may be inserted in the jaws and the jaws closed over the ring manually. While thus held, it is necessary to lock and cock the device by advancing the slide assembly |20 so that the roller bearings |1 and I8 engage the rea-r ends of the jaws and are held in that position. This means that the assembly |20 must be moved forwardly against opposition of the compression spring |23.

I provide for this by a manually actuatable camrarrangement which will next be described.

The rotatable sleeve or cocking ring |02 is mounted on the forward reduced end portion of the shell |00 which begins at the shoulder 2. This ring has an external knurled portion |6I to facilitate gripping thereof. The ring is riveted to a circular cam |62. 'Ihis cam has complementary inclined surfaces |63 and |64 each describing an arc almost of 180 degrees and terminating abruptly at |65 and |66 in diametrically opposite shoulders so that they in effect form a slot |61.

The faces of the cam are adapted to engage a pin |10 which is mounted transversely through a block I1| rigidly secured within the sleeve |2| and forming part of ith'e shiftable assembly |20. The pin |10 is adapted to move longitudinally of the shell within the limits of the slot |09 in the shell |00.

For locking and cocking the coupling, the ringl |60 is rotated approximately a half turn which causes the cam surfaces to engage the pin |10 thereby forcing the assembly |20 forwardly into the position shown in Figure 7.

When the cam reaches its peak of movement there is adequate clearance for the notched rear end of the trigger |25 to engage the latch pin |21. The trigger is assisted by a wire spring |15, and is overbalanced at the rear end in addition. The spring in the solenoid shifts the plunger rearwardly to move the rocker arm |28 toward the trigger so that the trigger comes to rest in the upper step |33 of therocker arm. The ring is rotated beyond the peak action of the cam so that the pin |10 is positioned in what I have described as the slot |61 which may be otherwise explained as the lowest depression in the cam, necessary for freedom of movement of the pin |10 when the coupling is again actuated for release.

Although I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details desclosed herein but is to be accorded the` full scope of the claims so as to embrace any and al1 equivalent devices.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A glider coupling comprising: a hollow tubular housing, pivotally mounted cooperating jaws on said housing for securing a tow cable, slidabley means conning said jaws in closed relationship, means operable for sliding said slidable means permitting'them to open and release said cable, and electrical means mounted inside said housing for actuating said sliding means.

2. A glider coupling comprising: a hollow housing member, jaws pivotally mounted at one end of said member and cooperating when closed to secure'a tow cable, slidable means supported by said member engaging said jaws to hold them in closed relationship, a spring tensioned to slide said slidable means out of engagement with said jaws whereby said jaws are permitted to open and release said cable, trigger means normally restraining said spring, and a solenoid actuated means adapted to free said trigger means from its restraint of said spring.

y3. A glider coupling comprising: a tubular sleeve, jaws pivotally mounted at one end of said sleeve and cooperating when closed to secure a tow cable, slidable means supported by said sleeve engaging said jaws to hold them in closed relationship, a spring within said sleeve tensioned to slide said slidable means out of engagement with said jaws whereby said jaws are permitted to open and release said cable, trigger means mounted in said sleeve which can be cocked to restrain saidk spring, -and a solenoid actuated means mounted within said sleeve to free said trigger means from cocked position to release said spring.

4. A glider coupling comprising: a tubular sleeve, jaws pivotally mounted at one end of said sleeve and cooperating when closed to secure atow cable, slidable means supported by said sleeve engaging said jaws to hold them in closed relationship, a spring within said sleeve tensioned to slide said slidable means out of engagement with said jaws whereby said jaws are permitted to open and release said cable, a trigger pivotally mounted in said sleeve one end being depressible to restrain said spring, a rocker arm pivotally mounted in said sleeve adapted to hold the opposite end of said trigger elevated to depress the spring restraining end, and a solenoid to shift Vsaid rocker arm and thereby remove support from the said opposite end of said trigger. v

5. In a glider coupling comprising pivotally mounted cooperating jaws for securing a tow cable, a slidable collar adapted to embrace said jaws to hold them closed, a yoke connected to said sleeve, and a spring normally urging said yoke to hold said collar in jaw yclosing position; an electrically actuated release mechanism comprising:4 a spring interconnected with said yoke opposing said rst named spring and having sufdetengo cient tension to overcome the `latterand shift said collar to jaw releasing position, means to restrain said second named spring, -and'a solenoid `actuated release cooperating with said means-to remove the restraining laction of same.

6. In 'a glider coupling comprising pivotally mountedcooperating jaws for securing a tow cable, a slidable collar adapted to embrace said jaws to hold them closed, a yoke connected to said 'sleeve, and a spring normally urging said yoke to hold said collar in jaw closing position; an .electrically actuated release ymechanism comprising: a spring interconnected with said yoke opposingsaid -rst named spring and having sufficient tension to-Fovercome theiaftter and shift said collar to jaw releasing position, a triggerto Vrestrain lsaid second named spring, and Jasolenoid actuated release cooperating -with said t-rig- 'ger to remove the restraining action of same.

7. In va glider coupling comprising pivotally mounted cooperating jaws for securing a tow oable, a slidable collar adapted to embrace said jaws to hold them closed, a yoke connected to said sleeve, and a spring normally urging `said yoke to hold vsaid collar in jaw `closing position; an `electrically actuated release mechanism comprising: a spring opposing ysaid rst named spring and having sufficient tension to overcome the latter and shift said collar to jaw releasing position, Va vshiftable yblock abutting said second named spring, a linkage interconnecting said `block Ikand said yoke, `a latching device restraining said block, and a solenoid Aoperated device for freeing said latching device.

8. Inv a glider coupling comprising -pi'votally mounted cooperating jaws Vfor securing a -tow cable, a slidable collar vadapted -to embrace said jaws to hold them closed, -a yoke connected to said sleeve, and a spring normally urging said yoke to hold said collar in jaw closing position; an electrically actuated 'release mechanism comprising: a spring opposing said Yfirst lnamed spring and having sufficient `tension to overcome the latter and shift said ,collar to jaw releasing'position, a shiftable block abutting said second named spring, a linkage interconnecting said block and said yoke, a pin on said block, a trigger engageable with said pin, a rocker arm adapted in one position to hold said trigger in engagement with said pin to restrain said block, and a solenoid operating said rocker arm to shift same to a second position in which said trigger is releaseable from said pin.

9. In a glider coupling comprising pivotally mounted cooperating jaws for securing a tow cable, a slidable collar adapted to embrace said jaws to hold them closed, a yoke connected to said sleeve, and a spring normally urging said yoke to hold said collar in jaw closing position; an electrically actuated release mechanism comprising: a spring opposing said first named spring and having sufficient tension to overcome the latter and shift said collar to jaw releasing position, a shiftable block abutting said second named spring, a linkage interconnecting said block and said-yoke, a pin on said block, a pivotally mounted trigger having one end face engageable with said pin in cocked position, a rocker arm adapted in one position to hold vsaid trigger end face in engagement with said pin to restrain said block in cocked position, a solenoid operating said rocker arm to -shift same to a second position in which said trigger end face is releasable from said pin, and said trigger embodying an elementengageable with said pin when said -blck isamoved to cooking position to rock said trigger to cocked position.

10. In a device of the character described including a jaw releasing mechanism comprising a spring actuated slidable member within a housing, a pivoted trigger adapted .to be cocked for `restraining said member against .the action of the spring, and a two step solenoid actuated rocker arm mechanism adapted to cock said trigger `by engagement of one step with said trigger and to spring said trigger by shifting said mechanism so that the second step engages the trigger.

a111. A coupling comprising: a housing, jaws lpivoted on said housing andclosable by spreading the rear ends of said jaws, a. slidable member adapted in -one position -to be interposed between ythe-rear ends of said jaws to'hold the-jaws closed, said member including two pins, each pin transversely disposed to one of said jaws and having a roller bearing thereon adapted to engage the rear end of the associated jaw, and means to slide said .member yfree of engagement with said jaws whereby same may-open.

'12. A coupling comprising: a housing, jaws pivoted on said housing and closable by spreadving-the rear endsrof said jaws, a slidable member adapted in one position to be interposed between the rear ends of said jaws to hold the jaws, closed, and -means'to slide said member free of vengagement with said jaws whereby same may open, sa-id means comprising a spring, means -to compress said spring into Vcocked position, a latching device for holding said spring cocked, and a releasing element to unlatchsaid device.

18; A coupling comprising; a housing, ljaws pivoted on said housing and closable -by spreading the rear ends -of said jaws, a slidable member adapted in one position to'be interposed between the rear ends vof said jaws to -hold the jaws closed, and -means to slide said member free of `engagement with said jaws vwhereby same may open, said .means comprising a spring, means to compress said spring into cockedposition includingfafcam bearing-on said housing and engaging 4a Ipart of 4said slidable member, a -latching device Vfor rholding said spring cocked, and a releasing element to unlatch said device.

14. A coupling comprising: a housing, jaws pivoted on said housing and closable by spreading the rear ends of said jaws, a slidable member adapted in one position to be interposed between the rear ends of said jaws to hold the jaws closed, and means to slide said member free of engagement with said jaws whereby same may open, said means comprising a spring, means to compress said spring into cocked position including a cam bearing on said housing and engaging a part of said slidable member, a manually operable ring rotatable on said housing and associated with said cam to rotate same, a latching device for holding said spring cocked, and a releasing element to unlatch said device.

15. A coupling comprising: a tubular housing, jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said jaws to open when retracted, a spring coacting between said housing and said member to retract said member, means to advance said member and compress said spring comprising a cam engaging a part or said member and rotatable beyond peak of cam action to free said member for retraction, a latching mechanism restraining said member at the peak of said cam action, and means for tripping said latching mechanism.

16. A coupling comprising: a tubular housing, jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said jaws to open when retracted, a spring coacting between said housing and said member to retract said member, vmeans to advance said member and compress said jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said jaws to open when retracted,"a spring coacting between said housing and said member to retract said member, means to advance said member and compress said spring comprising a cam engaging a part of said member and rotatable beyond peak of cam action to free said member for retraction, a latchving mechanism restraining said member at the peak `of said cam action, said mechanism including a trigger when in cocked position interv connecting said housing and slidable member and holding said member in advanced position, a rocker arm for holding said trigger in cocked position, and a solenoid for shifting said rocker arm to spring said trigger.

18. A coupling comprising: a tubular housing, jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said jaws to open when retracted, a spring coacting between said housing and said member to retract said member, means to advance said member and compress said spring comprising a cam engaging a part of said member and rotatable beyond peak of cam action to free said member for retraction, a latching mechanism restraining said member at the peak of said cam action, said mechanism including a trigger pivoted in said slidable member and when in cocked position engaging an element of said housing to hold said member in advanced position, and a solenoid actuated device for springing said trigger.

19. A coupling comprising: a tubular housing, jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said jaws to open when retracted, a spring coacting between said housing and said member to retract said member, means to advance said member and compress said spring comprising a cam engaging a part of said member and rotatable beyond peak of cam action to free said member for retraction, a latching mechanism restraining said member at the peak ofsaid cam action,`said mechanism including a trigger pivoted in said slidable member and when in cocked position engaging an element of said housing to hold said member in advanced position, a rocker arm on saidomember for holding said trigger in cocked position, and a solenoid for shifting said rocker arm to spring said trigger.

20. A coupling comprising: a tubular housing, jaws pivoted on said housing, a slidable member mounted in said housing holding said jaws closed when advanced and freeing said'jaws to open when retracted, a spring coacting between said housing and said member to retract said member, means to advance said member and compress said spring comprising a cam engaging a part of said member and rotatable beyond peak of cam action to free said member for retraction, a latching mechanism restraining said member at the peak of said cam action, said mechanism including a trigger when in cocked position interconnecting said housing and slidable member and holding said member in advanced position, a rocker arm for holding said trigger in cocked position, a solenoid for shifting said rocker arm to spring said trigger, and an auxiliary manually operated pawl to shift said rocker arm to spring said trigger.

JOHN F. DRESCHER. 

